1. Field of the Invention
The present invention relates to a suspended particulate matter measurement apparatus for collecting suspended particulate matter in the atmosphere and measuring the components of the collected particulate matter, and also relates to a suspended particulate matter measurement method that uses the suspended particulate matter measurement apparatus to measure the particulate matter.
2. Description of the Background Art
The recent studies indicate that sulfate ion is one of the main components of suspended particulate matter in the atmosphere. Epidemiologically, nitrate ion, sulfate ion, and acidity of suspended particulate matter are considered to be factors determining the toxicity of the suspended particulate matter (see, e.g., D. W. Dockery, et al., N. Engl. J. Med., 329, 1753-1759 (1993); hereinafter referred to as Non-Patent document 1).
As a suspended particulate matter measurement apparatus of conventional art, the applicant of the present invention has proposed a suspended particulate matter measurement apparatus for classifying and measuring total suspended particulate matter and fine suspended particulate matter (see, e.g., Japanese Patent No. 3574045; hereinafter refereed to as Patent Document 1). The conventional suspended particulate matter measurement apparatus is configured to include: a classification apparatus for classifying suspended particulate matter into coarse suspended particulate matter and fine suspended particulate matter; and calculating/recording means for calculating and automatically recording the amount of total suspended particulate matter and the amount of fine suspended particulate matter.
The suspended particulate matter measurement apparatus of the conventional art is capable of measuring the amount of total suspended particulate matter, the amount of fine suspended particulate matter, the amount of nitrate ion, and the amount of sulfate ion, which are contained in the atmosphere. However, the conventional suspended particulate matter measurement apparatus cannot automatically measure the amount of nitrate ion and sulfate ion contained in the atmosphere.